Java BLOB 資料的插入與讀取 操作

標籤：

package com.lw.database;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;/** * CREATE: *         CREATE TABLE IDCard ( id char(18),pic BLOB); * @author liuwei * Time: 2015年5月25日 下午3:22:26 */public class LOBTest {    protected static final String DEFAULT_URL = "jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=utf8";    protected static final String DRIVER_NAME = "com.mysql.jdbc.Driver";        private Connection connection = null;        public LOBTest() throws ClassNotFoundException, SQLException {        Class.forName(DRIVER_NAME);        connection = DriverManager.getConnection(DEFAULT_URL, "user", "password");    }        public void insert(String id,String path) throws SQLException, IOException {        PreparedStatement preparedStatement = connection.prepareStatement("INSERT INTO IDCard VALUES (?,?)");        preparedStatement.setString(1, id);        FileInputStream fileInputStream = new FileInputStream(path);        preparedStatement.setBlob(2, fileInputStream,fileInputStream.available());        preparedStatement.execute();    }        public void get(String id) throws SQLException, IOException {        PreparedStatement preparedStatement = connection.prepareStatement("SELECT pic FROM IDCard WHERE id = ?");        preparedStatement.setString(1, id);        ResultSet results = preparedStatement.executeQuery();        while(results.next()) {            FileOutputStream outputStream = new FileOutputStream("/Users/liuwei/temp.png");            InputStream inputStream = results.getBinaryStream(1);            int num = -1;            while((num=inputStream.read())!=-1) {                outputStream.write(num);            }            outputStream.flush();            inputStream.close();            outputStream.close();        }    }        public static void main(String[] args) throws ClassNotFoundException, SQLException, IOException {        LOBTest test = new LOBTest();        test.insert("78907656784323", "/Users/liuwei/Documents/bt_next_nor.png");        test.get("78907656784323");    }}

 

注意：

　　MySQL的四種BLOB類型 

　　　　類型  大小(單位：位元組) 

 　　　  TinyBlob  最大 255B

 　　     Blob  最大 65K 

 　　     MediumBlob  最大 16M 

 　　　  LongBlob  最大 4G 

插入映像的時候，注意像大小，映像超過該類型所能容納的最大位元組的時候，會報錯

 

Java BLOB 資料的插入與讀取 操作